The UN General Assembly is scheduled to vote on November 29 on a Palestinian resolution to upgrade their status at the world body.
Changing the status of the Palestinian mission from an "entity" to a "nonmember state" would mean indirect recognition of a Palestinian state, including the West Bank, Gaza Strip, and East Jerusalem.
The resolution is likely to pass with strong support expected from developing countries, but many European ones as well, including France.
A simple majority of the UN General Assembly's 193 members is needed for passage.
Russia and China are also expected to vote "yes."
A few countries are expected to vote "no," including Israel and the United States, which argue Palestinian statehood lies through direct talks.
Two senior U.S. officials met Palestinian Authority President Mahmud Abbas in New York on the eve of the vote in a final U.S. bid to convince the Palestinians to scrap their plan.
State Department spokeswoman Victoria Nuland voiced the U.S. position that true Palestinian statehood could not come through the United Nations.
"We've been clear, we've been consistent with the Palestinians that we oppose observer status in the General Assembly and this resolution," she said. "We made those points again and Deputy Secretary of State [William Burns] also reiterated that no one should be under any illusion that this resolution is going to produce the results that the Palestinians claim to seek -- namely, to have their own state living in peace next to Israel."
She repeated U.S. warnings that U.S. financial aid to the Palestinians could be impacted as a result of the UN action.
The United States blocked Palestinian efforts at the Security Council for full membership last year. And the United States cut funding to the UN cultural body UNESCO after it voted to grant full membership to the Palestinians in October 2011.
Hanan Ashrawi, a top official with the Palestinian Liberation Organization, had strong words for the countries voting against the resolution.
"We are moving ahead. Israel, the U.S., and a handful of countries will find themselves on the wrong side of morality, on the wrong side of justice and on the wrong side of the law," he said. "And we are very pleased to say that tomorrow midnight probably at our time you will see a [UN General Assembly] vote that will begin a process of historical redemption and healing in Palestine."
Being a "nonmember state" -- like the Vatican -- would allow the Palestinians to join international bodies, including the International Criminal Court (ICC) where they could seek action against Israel on war-crimes charges.
Ashrawi did not say the Palestinians would pursue action at the ICC but suggested it could be an option.
Analysts say strong European support will give a boost to the legitimacy of the Palestinian Authority and make it harder for the Israelis to take harsh retaliatory measures, including withholding customs duties collected by the Israelis on behalf of the Palestinians.
The vote comes after recent hostilities between Israel and militants in the Gaza Strip killed more than 150 Palestinians and six Israelis.
With reporting by AP, AFP, and Reuters